Background/Purpose: Approximately 15,000 Veterans are hospitalized for stroke each year. The ability to ?get out and about? in the community is considered to be either essential or very important to a majority of stroke survivors. Reduced levels of community ambulation and community participation, decreased satisfaction with levels of outdoor mobility and community reintegration, and perceived difficulty in coping with outdoor locomotion, have all been reported in individuals post-stroke. A return to community-based ambulation is a primary rehabilitation goal for many survivors of stroke. Accurately quantifying community mobility, therefore, is an important for post-stroke rehabilitation goal-setting and treatment planning. The criteria for the measurement of community ambulation has historically concentrated on mobility dimensions such as temporal and distance factors, as those were felt to best reflect the dimensions of the task. These measures, however, evaluate the individual in an unfamiliar environment, derive mobility from brief snapshots of walking performance, are not sensitive to subtle changes in function and do not directly assess an individual's free- living ambulation. There is a current unmet need for a measurement tool to objectively record ambulation in the real-world, outside of the clinic setting, that can parse ambulation in the home from true ambulation within the community. We will enroll 30 post-stroke ambulatory community-dwelling Veterans to validate and assess the feasibility of an innovative, wearable Global Positioning System (GPS)/Activity Monitor package to differentiate steps taken in the community versus steps taken in the home. Results will inform any adjustments to be made prior to using this sensor package in a full-scale study that will assess personal, social and physical factors that contribute to community walking. Subjects: Thirty individuals > 6-months post-stroke will participate. Additional study criteria include: 1) able to follow 3-step command, 2) gait speed > 0.4 m/s, 3) ambulatory without physical assistance, 4) no other neurological diagnosis, 5) no history of intermittent claudication, 6) no angina at rest or with minimal exertion, 7) no history of COPD, 8) not currently receiving physical rehabilitation services, 9) presence of a caregiver. Methods: To test the concurrent validity of the GPS/Activity Monitor package, participants will navigate a 300 meter combined indoor/outdoor walking circuit consisting of steps, ramps, curbs and sidewalks with the sensor package affixed to their nonparetic ankle, under direct observation of a physical therapist who will utilize a step counter, stop watch and field notes, to record steps taken, time and distance walked and participant location. To test the feasibility of this novel sensor package, participants will wear the package for seven days during free-living community ambulation. Participants will don the package when they arise and doff it at bedtime. They will keep a Trip Activity Log, to record when they leave their property, the length of time away and any walking they did. Following seven days, participants will return the sensor package to the study site and will complete Quality of Life and Perception of Use (with regard to the GPS/Activity Monitor) questionnaires. Outcome Measures: Our primary outcomes measures will be Steps per Day as measured by StepWatch Activity Monitor and location of those steps (inside the home vs. outside the home) as measured by a wearable GPS device. For our third exploratory aim, we will administer the Stroke-Specific Quality of Life questionnaire. Data Analysis Plan: To assess concurrent validity, Kappa statistics will calculate agreement between number of outdoor steps, time and distance traveled outdoors and participant location recorded by the GPS/Activity Monitor package and direct observation by research personnel. Feasibility will be assessed by calculating the percent time participants wore the sensor package and percentage of trips outside the home capture by the sensor package compared to trips recorded in the Trip Activity Log. Pearson correlation will test the relationship between daily steps taken inside, outside and total steps and Quality of Life.